(a) Field of the Invention
The present invention relates to an improved emulsifying system and method for mixing accurate ratios of two or more liquids to form an emulsion. Preferably, but not exclusively, the liquids are water and oil which are pressure regulated and the supply is isolated from a vented storage container which stores the emulsion to feed emulsion burning apparatus.
(B) Description of Prior Art
There exists a need to provide efficient means of mixing water and oil together to form an emulsion to feed burning apparatus whereby to reduce pollutants which are released in the atmosphere and which also reduce the efficiency of burning apparatus and associated devices. Further, by providing a water/oil emulsion, less oil is consumed by the burning system. Various chemicals and apparatus have heretofore been provided in an attempt to achieve such objectives. However, such known methods and apparatus have not proved to be entirely efficient and economical.
Surfactants are sometimes used to break down the surface tension of one of the fluids to be mixed together, whereby to enable the mixing to take place. Surfactants are usually expensive and require additional savings in the system construction whereby to justify the cost thereof. Also, it has been found that surfactants promote boiler and flue corrosion. The very fact that the surface tension is reduced, eliminates or diminishes the microexplosions which take place with an emulsion produced without surfactants. These microexplosions are important to the improved performance of burning emulsion.
It is also known to use sonic whistles or similar type devices together with high pressure pumps to produce a desired emulsion. However, known systems which use such devices do not provide means to reduce capacity in order to correspond to varying firing rates of burners, without reducing feed pressures. The reduction of feed pressures seriously reduces the effectiveness of this type of equipment thereby providing a drawback.
Another type of apparatus known is the piston type homogenizer which is used to produce emulsions from water and oil. These homogenizers, however, require very large amounts of horsepower, require frequent maintenance, and are expensive.
Another type of prior art device known is the ultrasonic reactor which is used to produce a water/oil emulsion. This equipment is, however, very expensive, and uneconomical. Also, such reactors are known to fail due to overpressure, startup with cold oil, etc. This type of system is susceptible to damage from external pressure sources.
Controlling water to oil ratio is very difficult because there is a reliance on standard control items which in themselves are not accurate while trying to proportion through the range of firing rates of a burner system. Known methods and devices, such as those described above, are also very costly.
Recirculating or circulating emulsion through a burner system has been very difficult, if not impossible to achieve, because of the problem of contaminating the straight oil with emulsion.